<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style>
			.box {
				position: relative;
			}
			
			.box>div {
				width: 100px;
				height: 100px;
				position: absolute;
			}
			
			.box>div:nth-child(1) {
				background-color: #f00;
				top: 10px;
				z-index: 15;
			}
			
			.box>div:nth-child(2) {
				background-color: #0f0;
				left: 20px;
				top: 20px;
				z-index: 20;
			}
			
			.box>div:nth-child(3) {
				background-color: #00f;
				left: 30px;
				top: 30px;
				z-index: 30;
			}
			
			.box>div:nth-child(4) {
				width: 140px;
				height: 140px;
				background-color: #ff0;
				left: 15px;
				top: 40px;
				z-index: 10;
			}
			
			
			
		</style>
	</head>
	<body>
		<section class="box">
			<div></div>
			<div></div>
			<div></div>
			<div></div>
		</section>
	</body>
</html>